Striker Alvaro Morata's 20 million euros move to Juventus has quickly turned sour after the Spaniard injured his knee in his first training session and was ruled out for seven weeks.

The 21-year-old, who completed his move from Real Madrid on Saturday, suffered a second degree injury to the medial collateral ligament in his left knee after being injured on Monday, the Serie A champions said in a statement on Tuesday.

"The forecast for a full recovery is of 50 days," the club said.

A highly-rated product of the Real youth academy, Morata came to the fore in the 2012-13 season, former coach Jose Mourinho's last at the club.

He scored eight goals in 23 La Liga appearances last season.

Even before the injury, he was expected to have a hard time breaking into the Juventus team where Carlos Tevez and Fernando Llorente formed an outstanding partnership in attack last season.